Posts Tagged ‘tri-tet-ten’
The batch of bureau cards last week included several cards from Europe and were probably the last I'll get for my Cycle 24 10m fun, using the homebrew Tri-Tet-Ten.
As mentioned previously, this rig was the culmination of wondering, for many many years, if I could get a single 6L6 to work well enough on 10m CW, using a 40m crystal ... quadrupling to 10m ... and still have enough useful output to work Europe! As well, the note would have to be 'acceptable' as I realized that any crystal chirping would be multiplied four times, during the quadrupling process.
The evolution of my eventual transmitter, is described in more detail here, where you can also hear what the tone sounds like. Suffice to say, the results were much more than I had ever hoped for and during the peak years of this past cycle, many enjoyable hours were spent on 10m CW with my one tube tri-tet crystal oscillator.
I guess I could always move down to 20m CW but, for me, this just doesn't have the same appeal or sense of satisfaction as using it on 10m or what I like to call, "the other magic band". Who knows what Cycle 25 will bring to 10m? I may get another chance yet, if the solar prognosticators are all wrong!
|courtesy: VK5TR http://www.users.on.net/~endsodds/
I spent a few hours yesterday, operating in the 'RAC Winter Contest'.
Originally, this contest began back in 1932, when QST excitedly announced a 'Canada-U.S.A. Contact Contest' to run in mid-January of that year.
The contest turned out to be extremely popular and has been run, in one form or another, ever since ... gradually becoming known as the 'VE-W Contest', sponsored by the Montreal Amateur Radio Club, and eventually by its modern name, with one version in July and a second in December.
As a teen-aged ham, the 'VE-W Contest' was always the highlight of the year as the contest format, much as it is today, made anyone with a 'VE' call as sought-after as AC4YN ... not the one in North Carolina!
Old-timers and DXers will remember the call, as it represented the rarest of all possible contacts at the time and only a very lucky few made contact with the low-powered station, high in the Himalayan mountains at the British mission encampment in Lhasa, Tibet, in the late 30's. Having an 'AC4' QSL on the wall anointed you bragging rights for life.
Another great aspect about the contest back then, as in most, was that stations exchanged real RST's and not the meaningless '599' of today's contest operation. It was always interesting to learn how my little station, nestled in the upstairs attic, was really sounding at the other end.
I decided to set up my homebrew 'Tri-Tet-Ten', 6L6 crystal oscillator, and give the contest a short try. Being unable to conveniently move around the band meant that I would be reliant on stations answering my CQs ... not something that normally happens with the little transmitter in typical contest QRM ... but the magical 'VE' factor would change all of that, I hoped.
I plugged-in the 15/20m plate coil and got out my old homebrew RF-sniffer / wavemeter. It was the first piece of gear that I built, as a new 15 year-old ham, and the poor man's spectrum analyzer has been in constant use ever since. Using the 40m crystal's third harmonic, I have found the wavemeter is the easiest way to avoid mistuning and quickly found myself with just over 5 watts of RF ready to go. A tune-up for 20m later, found the second harmonic producing about 10 watts of pile-up generating madness.
Nowadays, the rules have changed a bit, and 'VE-to-VE' contacts are worth more than 'VE-to-W' QSO's but for 'W's, the goal is still to work as many 'VE's as possible ... and call they did.
Over the period of a few hours, the Tri-tet did not disappoint, generating 206 callers, including PY, PJ and HP ... frequently generating pileups 4 and 5 deep. I didn't try 10m as by the time I got started, it was falling off and the 6L6's 4 1/2 watts of fourth harmonic output on 10m requires really good conditions to be heard very well.
Due to conflicts with other activities, this was the first RAC VE-W Party that I have operated in many years ... it's nice to see that apparently not much has changed since 1932!
My antenna farm sat on our high, peaked roof and consisted of groundplanes for 40m, 20m and 15m ... these were made of inexpensive galvanized drain pipe, about three or four inches in diameter. The 40m one was guyed and also had one end of my 80m dipole attached to it, which ran out across the yard and across the back lane, terminating on one of BC Hydro's wooden (telephone) poles. Every once in a while the telephone guys would take it off and toss it over the fence whereupon I would get out the ladder and re-attach it, where it would stay for another year or so.
For this weekend's CW party, I have put my 'Tri-Tet-Ten' on 20m, doubling from a 40m crystal to 14051.5, placing me pretty close to the Sprint's watering-hole QRG of 14050. I have had way too much fun with this simple one-tube radio since building it, mainly for 10m CW, in anticipation of the present solar cycle's peak years. Although it puts out almost 5W when quadrupling to 10m, I can get a whopping 13W from it on 20m, which is plenty of power to have some fun.
So far I've worked about 40 stations, all on CQ's, since I can't really QSY to answer others ... so if you are around this afternoon, please give me a call should you hear my little rig. It's a real nice change to hear non-machine sent CW for a change and fists ranging from one end of the scale to the other ... really a nice reminder of what the bands used to sound like when I first got on the air.
Sadly, I fear that my Tri-Tet-Ten has likely seen the last of its glory days of European 10m DX. It has been sitting, forlornly, on it's operating shelf beside my main station, for a few years now and has always been ready to spring into action whenever the winter F2 on 10m rolled-in. Although I anticipate more 10m F2 this coming fall, I don't think we'll get any barn-burner European openings as I have seen in the past. Conditions really need to be very good for the 6L6's 4 1/2 watts of 10m output to make it over the pole but over the past four winters, the one-lunger has worked over 100 Europeans on 10m F2.
Not being quite ready to throw in the towel on one of my favorite ever projects, over the past two nights I have sparked-up the tritet on 20m, which has been like the good old days in the evening ... strong signals over the pole peaking around 2130 local time.
As it did on 10m, the tritet did not disappoint! My first CQ (crystal controlled on 14031 kHz) was a pounced upon by two Europeans, eager to work a VE7. Over the two evenings, contacts were enjoyed with the following stations:
OE5FBL Haid, Austria
RV3LK Smolensk, Russia
UA2FT Polessk, Russia
RA2FAC Kaliningrad, Russia
RA1OD Kotlas, Russia
R3RR Tambov, Russia
DL1SXB Schwerin, Germany
UR5LCZ Pivdenne, Ukraine
MD0CCE Ramsey, Isle of Man
OK1KTI Huntirov, Czech Republic
IK1XPP Crescentino, Italy
All of the stations were worked on my crystal frequency (a very old 40m xtal doubling to 20m) of 14031 kHz and answered my CQ. At just under 10 watts output, the average signal report received was 579.
Interestingly, two stations gave me 'T' reports of less than 9 to (incorrectly) describe the slight chirp on the oscillator. In the RST system, anything less than a 'T9' should actually describe the degree of undesired modulation (usually A.C. ripple) and not chirp. The proper way of indicating chirp is to append the report with a 'C'. Since chirp is rarely heard on the airwaves anymore, it's understandable that some might not properly understand the 'T' part of 'RST'.
So it looks as though the Tri-Tet-Ten has earned the right to stay on the side operating shelf a bit longer ... but I'm not renaming it the 'Tri-Tet-Twenty' just yet!
Tri-Tet-Ten" to test out a long-held idea of actually working Europe on 10m, using just a single-tube tri-tet oscillator and a 40m crystal. I had no idea what amount of power might be obtained on 28MHz from a single 6L6 crystal-controlled oscillator, quadrupling from 40m to Ten. After building several configurations as well as trying five different tube types, I was pleasantly surprised to end up with almost five 'clean' watts of 10m RF on my 40m crystal's 4th harmonic! I suspected that the tone would be unusable but the tri-tet proved to be surprisingly good at isolating the oscillator from the output stage. Although chirpy, the signal is indeed usable and somewhat reminiscent of what so many 10m CW signals must have sounded like at one time.
Having completed the transmitter just in time for Cycle 24's hoped-for great 10m conditions, it turned out that only a couple of one-week periods over the past three winters where good enough to reach Europe. During the two "double-peaks" I worked many dozens of Europeans, all of them in response to my crystal-controlled CQ's, mostly on 28.042kHz.
Nobody was more excited than I, the first time I heard a reply from Europe....it was from G4RRA who, as fate would have it, recorded my signal on that early October morning.
There were a few mornings when I had long pileups and worked Europe for several hours, most of the time shaking my head in disbelief that such a simple transmitter could provide so much DX pleasure...but really of course, it was mostly the great performance of Ten....the "other magic band".
I really doubt that 10m will once again support European conditions good enough for my one-tuber but it's still fun to work the U.S. With Cycle 24 on the decline I was happy to see that F2 has returned to Ten once again and this week I sparked-up the tri-tet to enjoy the propagation.
My chirpy return to the band produced many enjoyable QSO's..... NG2T (NY), KD8IFJ (MI), K9DP (IN), KA2MLH (NY), W4NA (VA), N4OW (FL), K8NS (FL), N5AF (TX), WA5AFD (OK), K5TIA (TX), K9DX (IL) and VE3IKV/m, boldly travelling along the freeway at 120kph!
So....if you hear a chirpy CQ just a smidgen below 28.042, please.... give me a call!
Will I be lucky enough to squeeze out one last winter of tri-tet fun before having to move down to 15 or 20m? Time will tell....but somehow it won't be quite the same as riding that delicate 10m ether over the pole to Europe, on just one tube.
I was reminded this week of all the fun that the Straight Key Century Club (SKCC) guys are having when receiving a nice e-mail from Bill, W0EJ:
Since 2006, this 12,000 strong group of CW diehards have been doing their best to promote the magnificence of the mechanical key in everyday operation. With monthly operating events, awards, Elmering and an online sked page, there are plenty of fun activities for both newcomers and old hands to enjoy what was once the only way to send CW.
I can well recall tuning the CW bands as a newly-licenced teen in the mid 60's. Electronic keyers were just beginning to show up but the vast majority of amateurs still "pounded brass" with a straight key or with some type of bug. I held out for about two years before I parked my straight key and spent my Saturday job money on a brand new Vibroplex original, which I still use from time to time.
Getting back to Bill's mail....I was more than happy to grant permission to use the photograph of my little 6L6 Tri-Tet-Ten that I have had so much fun with over the past few winters on 10m CW during the peak of Cycle 24. I think their new 1000 Miles-Per -Watt award looks just great.....
....and here is what you need to do to earn one for your wall:
SKCC Introduces 1000 MPW Award
The SKCC is rolling out a 1,000 Miles per Watt Award, established to recognize the achievement of contacting another SKCC member using QRP power limits over longer distances.
A QSO must meet the qualifications of (Distance of QSO) / (Power Output in Watts) = 1,000 miles or more. Only the station applying for the award must operate at QRP levels. QSOs made on or after Sept. 1, 2014, are eligible.
For full details, see the award's main page.
Please check out the SKCC's homepage and consider signing-up...or drop by the K3UK SKCC Sked Page and get in on the fun....but, be sure to leave your keyer unplugged and enjoy some straight-key splendor!
|'29 Style Card
When I next became interested in mid-30's style construction, I decided it was time for another 'era-appropriate' card to match the transmitters. I began searching the web for vintage cards from the mid-30's and soon zeroed in on a card that I found particularly attractive...and from Canada as well.
Once again, Dennis came to the rescue and worked enthusiastically with me to try and duplicate the features and look of the VE4 card that I wanted.
|'35 Style Card
I think he did a super job once again and this past winter the new cards have gone out at a furious pace as I worked many new stations, all on 10m CW with my 6L6 Tri-Tet-Ten.
If you or anyone you know might be interested in a vintage style card (or any type of card) please get in touch with Dennis. I cannot speak highly enough about him and the quality of his work. You won't be disappointed.